Radiation sensitive electronic counting system



R. J. DWYER Filed Oct. 23, 1965 RADIATION SENSITIVE ELECTRONIC COUNTING SYSTEM Dec. 31, 1968 INVENTOR.

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ATTORNEYS RAYMOND J. DWYER United States Patent 3,419,725 RADIATION SENSITIVE ELECTRONIC COUNTING SYSTEM Raymond J. Dwyer, 4737 Secor Road, Toledo, Ohio 43623 Filed Oct. 23, 1965, Ser. No. 503,820 1 Claim. (Cl. 250-222) ABSTRACT OF THE DISCLOSURE The present invention relates to a counter, and more particularly to an electronic counting system employing a means for establishing a relatively wide field of light, the intensity of which is varied by a transient opaque object which varies the amount of light energy impinging on a photoelectric device, thereby effective to vary the output thereof.

It is an object of the present invention to produce an electronic counter which will efficiently count irregularly shaped objects, such as screws, washers, and the like, as well as regularly shaped objects, at a high rate of speed.

Another object of the invention is to produce an electronic counting system wherein a spherical concave mirror is utilized to reflect light from a single source in a relatively wide flat beam or field back to a photosensitive device.

Other objects of the invention may be realized by an apparatus comprising a source of light, a photosensitive device, a spherical concave mirror to reflect light from the source to the photosensitive device, the light from the mirror being in the shape of a relatively flat converging beam through which the elements to be counted are caused to pass, and means coupled to the photoelectric device for counting any changes in the intensity of the light impinging on the photoelectric device.

The above objects, as well as other objects and advantages of the present invention, will become apparent from reading the following detailed description, together with the accompanying drawings, in which:

FIGURE 1 is a side elevational view of the apparatus embodying the features of the invention;

FIGURE 2 is a sectional view taken along line 2-2 of FIGURE 1; and

FIGURE 3 is an end elevational view of the apparatus illustrated in FIGURES 1 and 2.

Referring to the figures, there is shown an article feeding apparatus, generally designated by reference numeral 10. The feeding apparatus, diagrammatically illustrated, is typical of a vibrational type capable of feeding or conveying small parts sequentially along a given path. The parts are caused to be sequentially fed from the left-hand portion thereof and will thereafter drop downward. As the parts drop downwardly, they will be effectively counted by the apparatus of the invention, which includes a main tubular housing 12, one end of which is closed by a cover 14. The other end of the tubular housing 12 is provided with a cover 16 having a horizontally disposed slot 18 formed therein. Secured to the bottom side of the tubular housing within the interior thereof is a base plate 20 which is secured thereto by a pair of suitable fasteners 22, such as screws, for example.

A light source, including an incandescent bulb, for ex- :ample, is mounted on the base plate 20 near the closed end of the tubular housing 12. Suitable electrical leads 26 are electrically connected to the light source 24 and are caused to be coupled to a remote source of electrical energy. The lead 26 is directed through a suitably disposed opening in the side wall of the housing 12 and then through a supporting upright vertically adjustable member generally indi- 3,419,725 Patented Dec. 31, 1968 cated by reference numeral 28. The member 28 is formed of two telescoping elements 30 and 32. A clamp 34 is employed to secure the base member in the desired vertical position. The entire assembly is supported by an integral base member 36.

A photosensitive element 40, such as a photoelectric cell, for example, is mounted within the interior of the tubular housing on the plate member 20 and is located near the end thereof having the slotted cover 16. The photosensitive element is coupled to an amplifier (not shown) through a pair of electrical conductors 42.

A spherical concave mirror 44 is mounted in spaced relation in front of the slotted plate 16 by a pivotally supported bracket 46. The bracket 46 includes a front plate 48 and a top plate 50. The upper edge of the front plate 48 and the downwardly turned front edge of the top plate 50 are spaced apart and therefore cooperate to effectively create a horizontally extending slot therebetween. The bracket 46 is pivotally mounted between the respective end portions of a pair of strap-like members 52 and 54 by a pair of pivot pins 56. The opposite ends of the straplike members 52 and 54 are suitably fastened to the outer side wall of the tubular housing 12 by fasteners 58.

It has been found that satisfactory results have been obtained by forming the mirror 44 if a spherical concave configuration having a focal point which is coincidental with the photosensitive element 40. It will be further appreciated that the length of the supporting straps 52 and 54 are of such a length to cause the reflective surface of the mirror 44 to be spaced from the photosensitive device 40 to a distance equal to the focal length of the concave spherical surface of the mirror. The vertical positioning of the focal point of the mirror 44 is achieved by rocking or pivoting the bracket 48 about the pivot pin 56'.

In operation, the light produced by the light source 24 will be directed along the line L (FIGURE 1), through the slot 18 and thence be caused to impinge on the mirror 44 through the slot formed by the upper edge of the plate 48 and the downwardly turned front edge of the upper plate 50. Accordingly, the mirror sees a ribbon of light from the source 24, the rays of which are substantially parallel with respect to one another.

Further, it will be seen that only a relatively small por tion of the overall reflecting surface of the mirror 44 is actually employed in the operation of the system.

The light which impinges upon the mirror 44 is then reflected back through the slot between the plates 48 and 50 to the focal point of the mirror which is coincident with the photosensitive device 40. The general pattern of this reflected light is schematically illustrated in FIGURE 2 by the broken lines R. The reflected light produces a relatively wide flat beam or field of light through which the parts falling from the conveyor 10' will pass. As the parts falling from the conveyor 10 pass through the field of light defined by the broken lines R, a shadow is cast upon the photosensitive device 40 causing an interruption in the current flow therefrom and accordingly eflfecting a signal through the leads 42 to the associated amplifier which in turn is electrically coupled to a mechanical counting device. Manifestly, as this occurs, the counting device registers a count and this procedure continues until the desired number of parts have been satisfactorily counted. It has been found that the relatively wide flat beam or field of light produced by the aforedescribed system is very efficient in producing the desired results.

It will be appreciated that with the system described above, the photoelectric device 40 will be effective to count a single part, regardless of its shape or configuration, only once as it passes through the field or beam of reflected light. The reason for such counting action is that as the part being counted traverses the light field, the

intensity or amount of reflected light impinging on the photoelectric device 40 is varied from the maximum amount impinging thereon with no interruption. Any variation of light from the maximum reflected light will cause the associated counting system to be inoperative. When a single part has completely traversed through the field of reflected light, the counting system is once more energized to effect a count. Also, in certain applications, as the part being counted is traversing the field of reflected light, the circuitry associated with the photoelectric device 40 is deenergized and in turn deenergizes the article feeding apparatus 10. Thus, no parts or articles will be fed by the apparatus 16 while another part is passing through the field of reflected light.

In accordance with the provisions of the patent statutes, I have explained the principles and mode of operation of my invention, and have illustrated and described what I now consider to represent its best embodiment. However, I desire to have it understood that, within the scope of the appended claim, the invention may be practiced other wise than as specifically illustrated and described.

I claim: 1. An apparatus for counting elements passing therethrough comprising:

an elongate hollow tubular housing disposed in approximately horizontal position, said housing having a slotted aperture at one end thereof; a light source disposed within said housing for directing light to pass out of said housing through the slotted aperture thereof;

a spherical concave mirror disposed in horizontally aligned spaced relation from the slotted aperture of said housing for reflecting light from said source to the interior of said housing through the slotted aperture thereof;

means above said concave mirror adapted sequentially to feed small parts to a point above and in advance of said mirror to drop by gravity in the space between the end of said tubular housing and said concave mirror;

a photoelectric device disposed within said housing at a distance from said mirror equal to the focal length thereof; and

means coupled to said photoelectric device for detecting any changes in the intensity of the light reflected from said mirror for rendering a mechanical counting device operative to count parts dropped in the space between the end of said housing and said mirror.

References Cited UNITED STATES PATENTS 2,769,374 11/1956 Sick 250221 2,816,479 12/1957 Sloan 250222 X 2,847,162 8/1958 Meyer 250--222 X 2,964,640 12/1960 Wippler 250-218 3,248,551 4/1966 Frommer 88-14 X WALTER STOLWEIN, Primary Examiner.

US. Cl. X.R. 235--92 

